Climate change is remapping where humans can exist on the planet. As optimum conditions shift away from the equator and toward the poles, more than 600 million people have already been stranded outside of a crucial environmental niche that scientists say best supports life.

In other words, 3 to 6 billion people, half of humanity, will be trapped outside of the liveable zone, facing extreme heat, starvation and death. This is to say nothing of the continued mass extinciton of other species.

Climate Crisis Has Stranded 600 Million Outside Most Livable Environment — ProPublica